#P4423. [BJWC2011] 最小三角形

    ID: 5153 远端评测题 1000ms 128MiB 尝试: 0 已通过: 0 显示难度省选/NOI− 上传者: 标签>2011递归北京分治排序

[BJWC2011] 最小三角形

Problem Description

Xaviera has encountered an interesting problem.

There are NN points on the plane. Xaviera wants to find the triangle with the minimum perimeter.

Because there are many points and they are distributed irregularly, Xaviera asks you to solve this problem.

To reduce the difficulty, triangles also include three collinear points.

Input Format

The first line contains an integer NN representing the number of points.

The next NN lines each contain two integers, representing the coordinates of a point.

Output Format

Output a single line containing the minimum triangle perimeter, rounded to 66 decimal places.

4
1 1
2 3
3 3
3 4
3.414214

Hint

Constraints: For all testdata, 3N2×1053 \leq N \leq 2\times 10^5.

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